Imaging systems such as a camera are commonly provided with an autofocus (AF) feature. As described in U.S. Pat. No. 7,782,392 B2, conventional electronic camera systems may provide an autofocus feature using either the contrast (e.g., blur) of the captured image or a determined depth value of an object within the field of view of the camera. The depth value may be determined using reflected light and principles of triangulation. In addition to providing an autofocus feature, automatic exposure control (AE) may also be provided to determine the brightness of the object and adjust exposure. Alternatively, as described in U.S. Pat. No. 6,568,809 B2, a desirable focal point for a binocular or camera may be determined by tracking the gaze of a user's eyes.
In certain applications, however, it may desirable to allow the user to override the autofocus (AF) and/or automatic exposure control (AE) feature. In this case, the user should be allowed to manually adjust a control element such as a focus or brightness control. When the image is out of focus, however, it may not be apparent to the user in which direction adjustment should be made. Accordingly, the user may adjust the control in the wrong direction initially before realizing the error and subsequently changing the direction of the adjustment. Alternatively, the user may adjust the control in the right direction, but overshoot the correct focal point so that a reversal of direction back to correct focal point is required. Such iterative type of manual adjustment, however, is time-consuming. Also, such iterative manual operation of an image control element may require the complete attention of the user so that the user is prevented from attending to other tasks at the time, such as when the camera is part of a robotic system and the user is manipulating one or more tools, as described, for example, in U.S. Pat. No. 6,424,885 B1.